Three20 - open url for a shared view controller
I know that if map a url with from:toViewController:
, then open that url will create a new view controller and if from:toSharedViewController
is used then a shared instance will be used.
But for example
[map from:@"tt://tabbar/(initWithString:)" toSharedViewController:[MyTabbarController class]];
TTOpenURL(@"tt://tabbar/string");
This will invoke something similar to
[[MyTabbarController allo开发者_高级运维c] initWithString:@"string"]
But what will be happened if TTOpenURL(@"tt://tabbar/somethingelse")
in called later?
Since a shared object is used so will the initWithString:
be called twice on a same instance?
The answer is : no. I.e., init will not be called on an already initialized instance, but a new instance will be allocated and initialized.
This is due to Three20 associating the object to its full URL, which in your case is either "tt://tabbar/string" or "tt://tabbar/somethingelse", so that when querying the TTURLMap
, no already existing object will be found and a new one will be instantiated. At least, this is true as of Three20 1.0.3. But I guess they have not changed this.
In my opinion, the shared controller mechanism is to be used in very specific cases, like for a setting view, and it should not be thought as a sort of Three20-implemented singleton. Each time I tried to rely on this for more "clever" usage of the TTURLMap, I found myself going back to a non shared controller.
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